STM32H7A3 ADC+DMA使用问题

STM32H7A3 ADC+DMA使用问题

问题1：DMA采用半字传输16位ADC值，用于存储ADC数据的数组一定是采集数的两倍，否则会产生ADC溢出的错误中断HAL_ADC_ErrorCallback，从而无法进入ADC采集完成中断HAL_ADC_ConvCpltCallback。具体为什么是两倍，网上有很多解释，有兴趣的可以去查一下。

问题2：在使用ADC+DMA采集的时候突然发现一个奇怪的现象，就是只要在程序的任何一个地方再申请一个全局变量，ADC就会出现错误中断HAL_ADC_ErrorCallback。最后发现程序没有什么问题，就怀疑和初始化顺序相关，然后就使用STM32CUBEMX配置了一下ADC+DMA，看一下配置出来的初始化顺序，然后改成和CUBEMX配置顺序一样的，这个问题就解决了。

void ADC_Init(void)
{  
    ADC_ChannelConfTypeDef sConfig = {0};
	
	AdcHandle.Instance = ADC1;
    AdcHandle.Init.ClockPrescaler = ADC_CLOCK_ASYNC_DIV2; 
    AdcHandle.Init.Resolution = ADC_RESOLUTION_16B; 
    AdcHandle.Init.ScanConvMode = ADC_SCAN_ENABLE; 
    AdcHandle.Init.EOCSelection = ADC_EOC_SINGLE_CONV; 
    AdcHandle.Init.LowPowerAutoWait = DISABLE; 
    AdcHandle.Init.ContinuousConvMode = ENABLE; 
    AdcHandle.Init.NbrOfConversion = 3; 
    AdcHandle.Init.DiscontinuousConvMode = DISABLE; 
    AdcHandle.Init.NbrOfDiscConversion = 1; 
    AdcHandle.Init.ExternalTrigConv = ADC_SOFTWARE_START; 
    AdcHandle.Init.ExternalTrigConvEdge = ADC_EXTERNALTRIGCONVEDGE_NONE; 
    AdcHandle.Init.ConversionDataManagement = ADC_CONVERSIONDATA_DMA_CIRCULAR; 
    AdcHandle.Init.Overrun = ADC_OVR_DATA_OVERWRITTEN; 
    AdcHandle.Init.OversamplingMode = DISABLE; 
    
    if (HAL_ADC_Init(&AdcHandle) != HAL_OK)
    {
    }
    
    if (HAL_ADCEx_Calibration_Start(&AdcHandle, ADC_CALIB_OFFSET, ADC_SINGLE_ENDED) != HAL_OK)
    {
    }
	
	
	
    sConfig.Channel = ADC_CHANNEL_3; 
    sConfig.Rank = ADC_REGULAR_RANK_1; 
    sConfig.SamplingTime = ADC_SAMPLETIME_387CYCLES_5; 
    sConfig.SingleDiff = ADC_SINGLE_ENDED; 
    sConfig.OffsetNumber = ADC_OFFSET_NONE; 
    sConfig.Offset = 0; 
    sConfig.OffsetRightShift = DISABLE; 
    sConfig.OffsetSignedSaturation = DISABLE; 
	HAL_ADC_ConfigChannel(&AdcHandle, &sConfig);
	

	sConfig.Channel = ADC_CHANNEL_7; 
    sConfig.Rank = ADC_REGULAR_RANK_2; 
    HAL_ADC_ConfigChannel(&AdcHandle, &sConfig);
	

	sConfig.Channel = ADC_CHANNEL_4; 
    sConfig.Rank = ADC_REGULAR_RANK_3; 
    HAL_ADC_ConfigChannel(&AdcHandle, &sConfig);
	

	sConfig.Channel = ADC_CHANNEL_9; 
    sConfig.Rank = ADC_REGULAR_RANK_4; 
    HAL_ADC_ConfigChannel(&AdcHandle, &sConfig);
	
	
    
    if (HAL_ADC_Start_DMA(&AdcHandle, (uint32_t*)adc_buf, 3) != HAL_OK)
    {
    }

}

void HAL_ADC_MspInit(ADC_HandleTypeDef* adcHandle)
{

  GPIO_InitTypeDef GPIO_InitStruct = {0};
  if(adcHandle->Instance==ADC1)
  {
    
    __HAL_RCC_ADC12_CLK_ENABLE();
    __HAL_RCC_DMA1_CLK_ENABLE();
    __HAL_RCC_GPIOC_CLK_ENABLE();

    GPIO_InitStruct.Pin = GPIO_PIN_0|GPIO_PIN_4|GPIO_PIN_5;
    GPIO_InitStruct.Mode = GPIO_MODE_ANALOG;
    GPIO_InitStruct.Pull = GPIO_NOPULL;
    HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
	
	
	ADC1DMA_Handler.Instance = DMA1_Stream1; 
    ADC1DMA_Handler.Init.Request = DMA_REQUEST_ADC1; 
    ADC1DMA_Handler.Init.Direction = DMA_PERIPH_TO_MEMORY; 
    ADC1DMA_Handler.Init.PeriphInc = DMA_PINC_DISABLE;
    ADC1DMA_Handler.Init.MemInc = DMA_MINC_ENABLE; 
    ADC1DMA_Handler.Init.PeriphDataAlignment = DMA_PDATAALIGN_HALFWORD; 
    ADC1DMA_Handler.Init.MemDataAlignment = DMA_MDATAALIGN_HALFWORD; 
    ADC1DMA_Handler.Init.Mode = DMA_CIRCULAR; 
    ADC1DMA_Handler.Init.Priority = DMA_PRIORITY_LOW; 
    ADC1DMA_Handler.Init.FIFOMode = DMA_FIFOMODE_DISABLE; 
    ADC1DMA_Handler.Init.FIFOThreshold = DMA_FIFO_THRESHOLD_FULL; 
    ADC1DMA_Handler.Init.MemBurst = DMA_MBURST_SINGLE; 
    ADC1DMA_Handler.Init.PeriphBurst = DMA_PBURST_SINGLE;
    if(HAL_DMA_Init(&ADC1DMA_Handler) != HAL_OK)
    {
    }

	__HAL_linkDMA(&AdcHandle, DMA_Handle, ADC1DMA_Handler);
	
    
    HAL_NVIC_SetPriority(DMA1_Stream1_IRQn, 2, 0);
    HAL_NVIC_EnableIRQ(DMA1_Stream1_IRQn);
  }
}

void HAL_ADC_MspDeInit(ADC_HandleTypeDef* adcHandle)
{

  if(adcHandle->Instance==ADC1)
  {
    
    __HAL_RCC_ADC12_CLK_DISABLE();
    __HAL_RCC_DMA1_CLK_DISABLE();

    HAL_GPIO_DeInit(GPIOC, GPIO_PIN_0|GPIO_PIN_4|GPIO_PIN_5);
  }
}


void DMA1_Stream1_IRQHandler(void)
{
    HAL_DMA_IRQHandler(&ADC1DMA_Handler);
}


void HAL_ADC_ConvCpltCallback(ADC_HandleTypeDef* AdcHandle)
{
  
}